Abstract: With monthly data of high temperature for the summer (June ～ August) of East China in 1961～2002, climatological characteristics of high temperature is discussed for cites in the region and a fairly complete time series is set up for the regional processes high temperature and unusually high temperature. The climatological characteristics of high temperature for 12 cities (Shijiazhuang, Nanjing, Fuzhou, etc.) in the region are studied. As shown in the observations, hot weather doesn't last long whether it be with high or low humidity, in Shijiazhuang, which is also marked with high extreme temperature, small diurnal mean wind speed and small diurnal mean relative humidity; hot and humid weather last relatively longer during unusually hot temperature periods in Nanjing and Fuzhou, which is marked with high extreme temperature, small diurnal mean wind speed and large diurnal mean relative humidity. Monthly mean insolation hours have been decreasing in summer in recent years. The subtropical high and continental transforming high in East Asia are two governing systems for high summer temperature in the Chinese cities. Strong and persistent, they are the main factors responsible for relatively more days of high temperature and more frequent in the east of China. On its basis, a monthly climate prediction model is set up using the generalized function and optimized subset regression. It is shown to predict monthly high temperature with miner errors. The model is stable and useful.